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<head><meta charset="utf-8"><title>Can const parameters affect variance? · general · Zulip Chat Archive</title></head>
<h2>Stream: <a href="https://rust-lang.github.io/zulip_archive/stream/122651-general/index.html">general</a></h2>
<h3>Topic: <a href="https://rust-lang.github.io/zulip_archive/stream/122651-general/topic/Can.20const.20parameters.20affect.20variance.3F.html">Can const parameters affect variance?</a></h3>

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<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122651-general/topic/Can%20const%20parameters%20affect%20variance%3F/near/222206592" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> isHavvy <a href="https://rust-lang.github.io/zulip_archive/stream/122651-general/topic/Can.20const.20parameters.20affect.20variance.3F.html#222206592">(Jan 10 2021 at 05:11)</a>:</h4>
<p>I'm assuming they cannot, or else we'd have a PhantomConst type instead of allowing them to be unused, but perhaps there's an edge case that allows them to do so?</p>



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<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122651-general/topic/Can%20const%20parameters%20affect%20variance%3F/near/222211462" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> lcnr <a href="https://rust-lang.github.io/zulip_archive/stream/122651-general/topic/Can.20const.20parameters.20affect.20variance.3F.html#222211462">(Jan 10 2021 at 08:00)</a>:</h4>
<p>they cannot</p>



<hr><p>Last updated: Aug 07 2021 at 22:04 UTC</p>
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